For anyone that is coming to SockJS directly from socket.io, I've built an event system on top of SockJS that has a similar API to socket.io. It's called ChuckT, and [like SockJS] it has both a client and server-side component.
Client: https://github.com/epixa/chuckt
Server (node): https://github.com/epixa/chuckt-node
The project is still very new, so I haven't finished the tests nor documentation, but the readmes on those repos have information about installation and usage.